Cookie stamp



FIG. 1 is a perspective view of a cookie stamp showing my new design;

FIG. 2 is a side elevational view thereof, the front and rear views being identical;

FIG. 3 is a top plan view thereof; and,

FIG. 4 is a bottom plan view thereof.

The broken lines are illustrative purposes only and form no part of the claimed design. 

The ornamental design for a cookie stamp, as shown and described. 